1. Field of the Invention
The present invention relates generally to a method and apparatus for manufacturing a laminate for a flexible printed circuit board (FPCB), and, more particularly, to a method and apparatus for forming a metal plated layer in manufacturing a laminate for an FPCB.
2.Description of the Related Art
With reference to FIG. 2, a conventional method of manufacturing a laminate for an FPCB is described. FIG. 2 is a view showing a conventional apparatus for manufacturing a laminate for an FPCB.
The conventional apparatus for manufacturing a laminate for an FPCB comprises a transferring system including an unwinding roller 2, a main drum 3 and a winding roller 4, all of which are provided in a vacuum chamber. In addition, an infrared heater 5 for pre-heating a polyimide film 1 and film guide rollers 7, 8, 9 and 10 are provided. In addition, a tie layer sputtering cathode 6a and a copper conductive layer sputtering cathode 6b are provided, so that a tie layer and a copper conductive layer are sequentially formed when the polyimide film 1 is in contact with the main drum 3.
In the manufacturing method using the apparatus for manufacturing a laminate for an FPCB, the polyimide film 1 is unwound from the unwinding roller 2 at a predetermined unwinding tension. Then, the polyimide film 1 is heated using the infrared heater 5 between the film guide rollers 7 and 8. The heated polyimide film 1 is guided around the roller 8. While the polyimide film 1 is in contact with the main drum 3, the tie layer is first formed on the polyimide film 1 using the tie layer sputtering cathode 6a, after which the copper conductive layer is formed on the tie layer by the copper conductive layer sputtering cathode 6b. Thereafter, the polyimide film 1 having the copper conductive layer formed thereon is guided around the rollers 9 and 10 and then wound on the winding roller 4 at a predetermined winding tension.
Subsequently, the polyimide film processed in the vacuum chamber is exposed to external air and undergoes a process of forming a copper plated layer by wet plating using an aqueous copper sulfate solution, which is not shown in the drawing.
However, the conventional method of manufacturing a laminate for an FPCB has the following problems. That is, since the polyimide film is exposed to external air to form the copper plated layer thereon, the polyimide film having the copper conductive layer thereon may be easily oxidized by external air, which negatively affects the subsequent processes. In addition, the polyimide film having the copper conductive layer thereon may be contaminated by dust present in the external air.
Further, when the copper plated layer is formed by a wet plating process, a chemical such as an aqueous copper sulfate solution for wet plating is used, resulting in environmental contamination.